When a display unit is switched on, sudden access to a power supply may cause unpredictable voltage fluctuations on some lines. For example, there might have been an undesired high voltage on a clock signal line coupled to a gate driving circuit before the display of an image is started. At this point, the high voltage on the clock signal line may cause a shift register unit (for example, transistors therein) in the gate driving circuit to malfunction. In the case where the gate driving circuit is integrated on an array substrate (GOA), it is difficult to produce additional filtering or protection circuits due to limitations of the manufacturing process. Accordingly, such a case is particularly likely to occur.
When the shift register unit in the gate driving circuit malfunctions, the power supply chip may be readily short-circuited, resulting in a high-current overload. The high-current overload, on the one hand, may readily damage the circuits and shorten the life of the display device and, on the other hand, will lead to a protective shut-down of the power supply chip, so that the display device may present a black screen after its power-on.
Therefore, there is still a need for improvements of an existing display device.